PREreview of The landscape of paediatric infectious disease exposure in a rural sub-Saharan Africa setting in Kilifi, Kenya: longitudinal serological analysis over two decades and priorities for future vaccine development

Foley et al's study titled "The landscape of paediatric infectious disease exposure in a rural sub-Saharan Africa setting in Kilifi, Kenya: longitudinal serological analysis over two decades and priorities for future vaccine development" presents significant public health implications, particularly in the context of introducing new vaccines and enhancing existing ones in the region under investigation. The research focused on addressing prevalent infectious diseases in Kilifi County, Kenya through the utilization of an indirect method involving antibody measurement. Despite the limitations associated with using antibody measurement for diagnosing infectious diseases, the study made efforts to minimize potential interference from maternal antibodies and antibodies resulting from previous infections.

Major comment

·         The rationale for this study is based on the limited research conducted in the field. It is essential to thoroughly review previous studies on pediatric infectious diseases in specific regions and study area to identify gaps and to explain the preference for seroprevalence over other laboratory methods.

·         The term 'rural' needs to be clearly defined to provide context for the study. It is important to determine whether the entire Kilifi County in Kenya can be classified as rural or if there are specific criteria that need to be met.

·         Including information on the types of vaccines administered in Kilifi County, Kenya would be beneficial for the study. Understanding the vaccination practices in the region can provide valuable insights into the prevalence and prevention of pediatric infectious diseases.

·         The clarity of page 6 lines 141-146 is lacking. Within the method section, it is necessary to provide a clear definition of infection, as mentioned in the manuscript, where multiple blood samples were obtained from a single participant over a period of 3 months. It is important to specify which of these samples were utilized to define infection and temporally stable infection.

·         Antibodies can suggest exposure to a pathogen, vaccination, or passive acquisition from the mother. It is advisable to incorporate the vaccination status of participants. What is the rationale behind selecting 38 pathogens for consideration? Why were other pathogens like GBS, HIV, TB, Syphilis, Hib, etc. not included in the study?

·         The information regarding where the study took place, the group from which the participants were drawn, the individuals included in the study, how participants were chosen, and the requirements for inclusion were not adequately described.

·         Was consent obtained for this procedure, and what was the amount of blood collected (assuming it was a blood sample)? Additionally, could you provide details on how and from where the blood sample was obtained?

·         The results section lacks sufficient socio-demographic information about the participants, such as their sex, nutrition status, vaccination status..etc.

·         The manuscript lacks a clear definition of the term "pediatric," as it seems to overlap with the categories of infants and newborns. It is essential to provide a precise and distinct definition for each of these terms to avoid any confusion or ambiguity in the text.

·         Monitoring infants over time and tracking antibody levels may not provide a complete picture of the infection landscape, as existing antibodies can interfere with the results. It is important to take into account different infants at different time, as interference from existing and maternal antibodies can impact the accuracy of the findings. Additionally, there are various factors that may prevent infants from producing antibodies, potentially leading to false negative results.

·         On page 12, lines 307 to 311 of the discussion, it is possible that the interpretation may not be accurate, as a decrease in antibodies could indicate susceptibility to infection. It is important for vaccinations to maintain a sufficient level of antibodies in the bloodstream to protect against the specific pathogen targeted by the vaccine.

·         In cases where participants test positive for a certain condition or disease, it is crucial to provide appropriate support, counseling, and medical care.

·         Is it ethically justifiable to collect several blood samples from one participant?

Minor comments

·         Page 5 line 116 was the PCR used? Line 118 what does pl stand for in 100/pl?

·         It is recommended to incorporate both frequency and percentage instead of just percentage in order to enhance clarity in the abstract and results section.

·         The placement of the table heading at the top would enhance the overall organization and clarity of the information presented.

Competing interests

The author declares that they have no competing interests.